Process for breaking petroleum emulsions



Patented July 18, 1944 PROCESS FOItfiBREAKING PETROLEUM MULSIONS Melvin De Groote, University City, and Bernhard Keiser,

lite Corporation, Ltd.,

Webster Groves,\Mo.,

assignors to Petro- Wilmington, Dcl., a

corporation of Delaware Serial No.

8 Claims.

This invention relates primarily to the resolutionof petroleum emulsions.

One object of our invention is to provide a novel process for resolving petroleum emulsions of the water-in-oil type, that are commonly referred to as cut oil, roily oil, emulsified oil, etc., and which comprise fine droplets of naturallyoccurring waters or brines dispersed in a more or less permanent state throughout the oil which constitutes the continuous phase of the emulsion.

Another object is to provide an economical and rapid process for separating emulsions which have been prepared under controlled conditions from mineral oil, such as crude petroleum and relatively soft waters or weak brines. Controlled emulsiflcation and subsequent demulsification under the conditions just mentioned, is of significent value in removing impurities, particularly inorganic salts, from pipeline oil.

The compounds used as the demulsifying agent of our process, are esters .of sulfosuccinic acid, or the obvious chemical equivalent thereof, for example, sulfometh-ylsuccinic acid, in which at least one of the alcoholic compounds supplying an ester radical is an oxyalkylated acidyl-aryl-sulphonlmid.

Reference is made to U. S. Patent No. 2,072,085, datedMarch 2, 1937, to De Said patent discloses, among other demulsiflers, the type of compound which may be exemplified by the formula:

Cation. S O:.CH.C 0.R4

' CH,.COO.R;

in which R4 and R5 represent organic radicals derived by dehydroxylation of an alcoholiform hydroxyl-containing organic compound, with the proviso that the molecular weight range must be within the limits of 270 and 2700. The compounds are not limited to sulfosuccinates, but it is pointed out therein that a number of obvious chemical equivalents may serve with equal effectiveness. It is particularly to be noted that in this instance all reference to succinic acid or sulfosuccinates is intended to include as the absolute chemical equivalent in each and every instance methylsulfosuccinic acid and methylsulfosuccinates, i. e., compounds derived from citraconic acid or citraconic anhydride, instead of being derived from maleic acid or maleic anhydride. as described in said aforementioned De Groote and Keiser Patent No. 2,072,085. This applies particularly to the hereto appended claims.

In view of what has been said, it appears pertinent at this point to describe the oxyalkyl- Groote and Keiser.

' also applies to similar No Drawing, Application May 25, 1942,

ated acidyl-aryl-sulphonimids which furnish the radical indicated either by R4 or R5. The oxyal- 'kylation products, i. e., alcoholic bodies employed for dehydroxylation, are derived by oxyalkylation of compounds sometimes referred to as acidyl-aryl-sulphonimids. (See U. S. Patent No. 1,145,499, dated July 15, 1915, to Biickel.) Such sulphonlmids represent the product obtained by the introduction of two acyl radicals into the ammonium radical, one acyl radical being derived from a high molal detergent-forming "monocarboxy acid, and the other acyl radical being derived from an aryl sulfonic acid. Since the word acyl can properly be employed to describe both such acidic radicals, it is convenient to use the word "acidyP in a limited sense to refer to the acyl radical derived from a carboxy acid. The expression detergent-forming monocarboxy acids has been frequently employed in the literature to designate certain high molol acids having at least 8 and not more than 32 carbon atoms, and characterized by the fact that they combine with alkali to form soap or soaplike materials. The commonest examples are higher fatty acids derived from animal, vegetable, or marine sources. Other well-known examples include resinic acids, such as abietic acid, naturally-occurring petroleum acids such as those obtained by the oxidation of petroleum hydrocarbons, waxes and the like, and from certain naturally-occurring waxes. Such monocarboxy detergent-forming acids may be cyclic or acyclic. They may be saturated or unsaturated. Included also are derivatives which'do not eliminate the soap-forming property and which are obviously chemical equivalents of the unmodified acid. For instance, chlorinated oleic acid will serve as satisfactorily as oleic acid. Hydrogenated abietic acid is as satisfactory as the material prior to hydrogenation. Brominated naphthenic acid is as satisfactory as the napthenic acid itself. This derivatives obtainable from oxidized petroleum acids, wax acids, etc.

The aryl group may be monocyclic or polycyclic. In the polycyclic type the rings may be separated or fused. One or more alkyl radicals may be substituted in aromatic nucleus, for instance, dew rivatives may be obtained from toluene, xylene, cymene, methylnapthalene, diisopropyl-naphthalene, amylated naphthalene, and similar aromatics, in which the alkyl side chain may contain as. many as twenty carbon atoms. Other non-functional substitutents may also be prescut, The usual procedure is to react the selected aromatic compound with chlorsulfonic acid. or

. Patent No. 2,278,167, dated a quantitative yield imid. This procedure is so simple that it may less than 6 carbon atoms.

on the water bath in use any other suitable reactant to obtain the sulphonchloride. The sulphonchloride is then reacted with'ammonia to yield the sulphonamid.

As to a more complete list of suitable aromatic compounds, see U. S. Patent No. 2,248,342, dated July 8, 1941, to De Groote and Wirtel. This patent includes, among others, aromatic compounds obtained by introducing the octadecyl radical into the aromatic nucleus. Such radical can be introduced into benzene, naphthalene, diphenyl or into .a substituted benzene, a substituted naphthalene, or a substituted diphenyl.

Another procedure for obtaining aromatic sulphon-chlorides depends upon reaction with the corresponding sulfonic acid, certain nonmetallic halides, such as sulfurchlorides, or phosphorous chlorides being employed. One can prepare numerous substituted aromatic sulfonic acids in the manner described in U. S. March 31, 1942, to It is, of course, underunsubstituted aromatic sulfonic employed, and in fact, in some instances, are available as inexpensive by-products. The manufacture of the acyl chlorides presents no particular difliculty, especially when manufactured from high molal saturated noncarboxy acids. Reference is made to the manu- De Groote and Keiser. stood that acids may be facture from saturated fatty acids, from naphthenic acids, wax acids obtained from naturally-occurring waxes, oxidized petroleum acids, etc. Some'of the procedures employed for preparing the high molal acyl chlorides are not as satisfactory when unsaturated 'acids such as oleic acids are employed. Thus, sulphurchloride may serve satisfactorily for preparing the acyl chloride from stearic acid, but is not as satisfactory, if oleic acid is used, Phosphorus chlorides, for instance, phosphorus pentachloride,

may be used equally satisfactorily, as a rule, with either saturated acids, or monoethylenicacids. The same is true of thionyl chloride. As to such procedures, see aforementioned Biickel patent. When the high molal acids are of the polyethylenic type, or contain some other functional group, in addition to a single ethylene linkage, other ,difliculties may be encountered and special methods may be required.

When a sulphonamid, particularly a monocyclic sulphonamid free from nuclear substituted alkyl radicals, on ha ng, at the most, short chain alkyl radicals present, is treated with suitable acidyl chloride, one obtains practically of the acidyl-aryi-sulphonbe readily illustrated by the procedure described in the aforementioned .Biickel patent. The short alkyl chain or chains preferably have Acmvn-Ann-Surrnommrn Example 1 98 kilos of sodium benzenesulfonamid are heated in an oil bath for about 1-2 hours at about 100-120" 0., with 152 kilos, of stearic acid chlo-' crystallized from carbon atoms and not radical obtained from a high molal the evolution of hydrochloric acid ceases. Whi alcohol the product thus 01 tained melts at 100-102 C.

Thus, in view of what has been said, it is oi vious that one can readily obtain acidyl-ary sulphonimids of the type:

a R. n

ai as o, .N Ra R in which R1, R2 and R3 represent hydrogen atom or alkvl radicals containing one to twenty car bon atoms. R is an aromatic nucleus of th mbnocyclic or polycyclic type, and R is an acidy detergent at least 1 more than 32 carbon atoms that if an acidyl-aryl-sulphon imid ofthe kind above described is treated witl an oxyalkylating agent in the customary manner employed to oxyalkylate a phenol, a higl molal acid, or'the like, one obtains a varieti of valuble intermediates which may be waterinsoluble, or water-miscible, or water-soluble, depending upon the nature of the oxyalkylating agent used, and the molar proportion of oxyalkylating agent to sulphonimid. The presence of the two acyl radicals, one of which is a sulfonyl radical, in the sulphonimid molecule, makes the compound acidic. Such compounds combine with alkalles to give salts. Compare with the forming monocarboxy acid having We have found well-known Hinsberg reaction. Thus, essentially,

the same procedure may be Patent No. 2,208,581, dated July 23, 1940, to Hoefielmann. Briefly stated, the procedure employed is to treat the anhydroussulphonamid with a suitable alkylating agent containing a reactive ethylene oxide ring. As typical examples of applicable compounds may be men- ,tioned glycerine epichlorhydrin, glycide alcohol,

ethylene oxide, propylene oxide, butene-Z-oxide, butene-l-oxide, 'isobutylene oxide, butadiene oxide, butadiene dioxide, chloroprene oxide, isotype of oxylation products, in which a comparaanhydride.

' products 85 kilos of para-toluenesulfonamid are heated I presence of an indifl'erent solvent such, for instance, as carbon tetrachloride, with137 kilospalmitic acid chloride, until tively small amount of olefine oxide is used per mole of adidyl-aryl-sulphonimid. Indeed, reaction in molecular proportions, i. e., one mole of the oleflne oxide, per mole of imid supplies a suitableintermediate for subsequent conversion into a suifosuccinate, insofar that minimum oxyalkylation is suflicient .to introduce an alcoholic radical. Our preference, then, is to convert such water-insoluble oxyalkylation products into sulfosuccinates, and it is to be emphasized again that' this includes methylsulfosuccinates, i. e., derivatives of citraconic acid or However, one may convert the water-miscible oxyalkylation products, and for that matter, one may convert-the oxyal lation which are already water-soluble. Peculiarly enough, in the latter case such products sometimes exhibit increased efiectiveness as demulsifiers and also as emulsifiers.

In a general way, the oxyalkylating agent per mole'of sulphonimid, the greater the hydrotropic andhydrophile proprefer to employ lm'ger the proportionoi" portions. Thus, to moles of ethylene oxide per mole of sulphonimid greatly enhances such properities. If 20-60 moles of the oxyalkylating agent, particularly ethylene oxide, is employed,

,one obtains an intermediate of pronounced Ra R in which all the characters have their previous significance and n may represent any number from 1 to 60.

Inview of what has been said, it hardly ap-' pears necessary to include examples of the intermediate product beyond stating that oxyalkylation can generally be conducted under mild conditions of reaction. For instance, a temperature of 100-125" C. is usually satisfactory; sec- 'ondly, pressure of less than 200 pounds per square inch gauge pressure is usually satisfactory, the reaction may take place in a comparatively short period, for instance, two hours or less, but in other instances, as long as twenty hours may be employed. The reaction is conducted by using a suitable apparatus that insures intimate contact between the oxyalkylating agent and the sulphonimid. After the introduction of the first molecule of ethylene oxide or oxyalkylating. agent, acidity has disappeared, and the subsequent stages are sometimes suitably catalyzed by the presence of a small amount of alkali, such as caustic soda, sodium methylate, soap, or the like, which may be present to the extent of one tenth of 1% to one-half of 1%. Compare with the oxyalkylation of high molal alcohols.

OXYALKYLATED ACIDYL-ARYL-SULPHONIMID Example 1 Stearyl benzene sulphonimid sodium salt is dissolved in any suitable solvent, such as benzene or alcohol, and treated with dry hydrochloric acid gas so as to liberate the imid with the precipitation of salt. The salt is filtered off and the solvent evaporated. One pound mole of the imid so obtained is treated with one pound mole of ethylene-oxide so as to produce the corresponding substituted nitrogen-linked hydroxyethyl stearyl benzene sulphonimid.

OxYALKYLA'rEn AcrnYL-ARYL-SULPHoNIMIo Example 2 The substituted imid obtained in the manner described in the preceding example is mixed with two tenths of 1% of sodium methylate'and then subjected to further oxyethylation with 5 pound moles of ethylene oxide for each pound mole of the substituted imid.

OXYALKYLATED ACIDYL-ARYL-SULPHONIMID Example 3 The same procedure is followed as in the preceding example, except that 10-20 pound moles of ethylene oxide are used for each pound mole of the substituted imid.

OXYALKYLATED ACIDYL-ARYL-SULPHONIMID Example 4 Palmityl paratoluene sulphonimid obtained in the manner previously described, is substituted for stearyl benzene sulphonimid in Examples 1-3, preceding.

OXYALKYLATED ACIDYL-ARYL-SULPHONIMID Example 5 The same procedure is followed as in Examples 1-3, preceding, except that the sulphonimid is derived from mixed high. molal, fattyacid chlon W V -mixture of fatty acids, and especially, from the mixture obtained by the hydrogenation of naturally-occurring fats or oils. For instance, unsaturated naturally-occurring oils, such as olive oil, teaseed oil, soyabean oil, cottonseed oil, etc. may be hydrogenated and then subjected to saponifioation or= hydrolysis. The mixture of fatty acids so obtained or the mixture obtained from palm oil, or palm kernel oil, may be converted into a corresponding acyl chloride and employed in the present instance. Attention is again directed to the fact that it is our prefer ence to use an oxyalkylating agent having not over 4 carbon atoms, 1. e., ethylene oxide, propylene oxide, butylene oxide, glycidol, and methyl glycidol.

Reference is again made to U. S. Patent No. 2,072,085, for a complete description as to the conventional method or means for manufacturing sulfosuccinates and methylsulfosuccinates of the kind described. In the previous formula reference has been made to a cation. Usually, such cation is the sodium atom, for the reason that sulfosuccinates are most readily prepared by first preparing the ester of maleic acid, or methyl maleic acid and treating such ester with a bisulfite. Since sodium bisulfite is more readilyobtainable than potassium bisulfite, or some other sulfite, it is generally employed. As is well known, it is possible to use sulfurdioxide gas in the presence of the base, instead of bisulfite. The base may be an amine, such as triethanolamine, amylamine, benzylamine, cyclohexylamine, etc. If one desires to produce the type of compound, and this is a preferred type, in which the radicals R4 and R5 are both derived by dehydroxylation of an oxyalkylated acidyl-aryl-sulphonimid, then one need only follow the procedure specifically outlined in said aforementioned De Groote and Keiser Patent No. 2,072,085. Such procedure is illustrated by the following examples:

Dr( OXYALKYLATED ACIDYL-ARYL'-SULPHONIMID) MALEA'IE Example 1 Two pound moles of an oxyalkylated acidylaryl-sulphonimid of the kind exemplified by Example 1, preceding, is converted into the dimaleate in the manner described in the aforementioned U. S. Patent No. 2,072,085.

DI(OXYALKYLATED ACIDYL-ARYL-SULPHONIMID) MAL-BATE Example 2 The same procedure is followed as in Example 1, preceding, except that the oxyalkylated acidylaryl-sulphonim-id employed is of the kind exemplified by Examples 2-6, preceding, instead of Example 1, preceding.

DI(QXYALKYLATED ACIDYL-ARYL-SULPHONIMID) MALEATE Example 3 The same procedure is followed as in Examples 1 and 2, preceding, except that citraconic anhydride, i. e., methyl maleic anhydride, is substituted for maleic anhydride.

SULFosUccmA'rr. COMPOUND I Example 1 One pound'moleof a maleated ester described under the three previous headings is treated with one pound mole of sodium bisulfite in the manner described in the aforementioned U. S. Patent No. 2,072,085.

smrosuccrm'rs CQMPOUND Example 2 The same procedure is followed as in Example found on page 2 of said patent, right hand side,-

lines 43 to 72, inclusive, Where the following are enumerated: Monohydric alcohols, such as propyl alcohol, butyl alcohol, amyl alcohol, hexyl alcohol, octyl alcohol, decyl alcohol, duodecyl alcohol,

such as oleyl alcohol; 'polyhydric alcohols, such as glycols, ethylene glycol, for example, glycerol.

polyglycerols, etc.; ether alcohols, such as diethylene glycol butyl ether, etc.; polyhydric alcohols having at least one remaining free hydroxyl, in

which one or more hydroxyl has been previously reacted with'a suitable acid, such as monoricithe equivalent bodies derived from polyglycerols; acid alcohols, such as hydroxystearic acid, ricinoleic acid, polyricinoleic acid, triricinolein, etc.; polyhydric alcohols, in which one or more dibasi'c carboxy acid residues have been introduced, such as a phthalic acid residue, a maleic acid residue, an oxalic acid residue, etc. (such polyhydric alcohol bodies may be employed, providing a free hydroxyl remains); cyclo-alcohols, such as phenoL-cresol, xylenol, naphthol, etc.; aralkyl alcohols, such as benzyl alcohol; heterocyclic alcohols,

such as furfuryl alcohol, etc; mixed isomer forms of the various alcohols, such as mixed amyl alcohols, etc. By way of illustration, the following examples are included:

MIXED MALEATES Example 1 One pound mole of octyl and maleate is reacted with one pound mole of an oxyalkylated acidyl, aryl-sulphonimid of the kind exemplified stearyl alcohol; unsaturated monobasic alcohols, 1

nolein, diricinolein, monostearine, mon'o-olein, or

' limited oil-solubility. However, since such reagents are sometimes used in a ratio of 1 to have solubility within the concentration emacid oil, cresol, athracene oil, etc.

by Example 1-, preceding, so as to eliminate one mole of water andobtain the dimaleate; The procedure employed is that described in the aforementioned U. S. Patent No, 2,072,085.

MIXED MALEA'I'ES Example 2 The same procedure is followed as in the precedingexample, except that one employs an oxyalkylated acidyl-aryl-sulphonimid of the kind exemplified by Examples 2-5, preceding, instead of Example 1, preceding.

MrxEi) MALEATES Example 3 The same procedure isfollowed as in the two examples immediately preceding, except that the compound is prepared from citraconic anhydride, instead of maleic anhydride.

SULFOSUCCINATE COMPOUND I Example 3 The same procedure is followed as in sulfosuccinates, Example 1 and 2, preceding, i. e., the

vent, such as water; petroleum hydrocarbons,

such as gasoline, kerosene, stove oil, a coal tar product, such as benzene, toluene, xylene, tar Alcohols, particularly aliphatic alcohols, such as methyl alcohol, ethyl alcohol, denatured alcohol, propyl alcohol, butyl alcohol, hexyl alcohol, octyl alcohol, etc., may be employed as diluents. Miscellaneous solvents, such as pine oil, carbon tetrachloride, sulfur dioxide extract obtained in the refining or petroleum, etc., may be employed as diluents. Similarly, the material or materials herein described, may be admixed with one or more of the solvents customarily used in connection with conventional demulsifying agents. Moreover, said material or materials may be used alone, or in admixture with other suitable wellknown classes of demulsifyingagents.

It is well known that conventional demulsifying agents may be used in a water-soluble form, or in an oil-soluble form, or in a form exhibiting both oil and water solubility. Sometimes they may be used in a form which exhibits relatively 10,000, or 1 to 20,000, or even 1 to 30,000, such an apparent insolubility in oil and water is not significant, because said reagents undoubtedly ployed. This same fact is true in regard to the material or materials herein described.

We desire to point out that the superiority of the reagent or demulsifying agent employed in our herein described process for breaking petrolem emulsions, is based upon its ability to treat 1 certain emulsions more advantageously and at a somewhat lower cost than is po'ssiblewith other available demulsifiers, or conventional'mixtures thereof. It is believed that the particular demulsifying agent or treating agent herein described will find comparatively limited application, so far as the majority of oil field emulsions are concerned;- but we have found that such a demulsifying agent has commercial value, as it will economically break or resolve oil field emulsions in a number of cases which cannot be treated as easily or at so low a cost with the dem'ulupon the emulsion to be treated, in any of the various ways, or by any of the various apparatusnow generally used to resolve or'break petroleum emulsions with a chemical reagent, the above procedure being used either alone or in combination with other demulsifying procedure, such as the electrical dehydration process.

Once more reference is made to U. S. Patent No. 2,072,085 in regard to the reference that the molecular weight range be within certain designated limits.

In reviewing what has been said, it is necessary that there be a differentiation in regard to the ,molecularweight of the compounds herein contemplated, as compared with thosecontemplated in the aforementioned U. S. Patent No. 2,072,085. The minimum molecular weight in the present instance is 536. As, for example, in the preceding formula, where the cation is the NH4 radical, and R4 is a methyl radical, and R5 is obtained from one mole of benzene-sulphonimid reacting with one mole of the acylchloride derived from ethyl hexenoic acid and one mole of ethylene oxide as the alkylating agent. Since the alcoholic residue containing the sulphonimid radical may be derived from polycyclic compounds, and since more than one side chain may be introduced, having for example, 18 carbon at- ,oms, and since the group that introduces the oxyalkyl radical may repeat itself, a large number of times, and since the acidyl group may be derived from montanic acid, it is obvious that reviewing the limits stated, one could readily obtain a compound having a molecular weight range as high as 3,000, or even higher. Consider, for example, an instance where the oxy-butylene group is introduced a large number of times, for instance, 40 or more times. With this in mind,

it will be noted that the molecular weight range of compounds of the kind herein contemplated assuch and as demulsiflers, is concerned with the range of 536 to approximately 5,000.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is:

1. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a chemical compound within the molecular weight range of 536 to approximately 5,000, and of the formula:

CatlomB O:.CH.CO 0.12"

in which R" represents an alcoholic radical and at least one occurrence of R" being the dehydroxylated residue of an oxyalkylated derivative of an acidyl-aryl-sulphonimid of the formula:

in which R is an aromatic nucleus, and R is an acidyl radical obtained from a high molal detergent-forming monocarboxy acid having at least 8 carbon atoms and not more than 32 carbon atoms; said derivative being obtained by means of an oxyalkylatin'g agent having a reactive ethylene oxide ring.

2. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a chemical compound within the molecular weight range of 536 to approximately 5,000, and of the formula:

Cation. S Oa.CH.C O O.R

UH2.COO.R"

in which R." represents an alcoholic radical and at least one occurrence of R." being the dehydroxylated residue of an oxyethylated derivative of an acidyl-aryl-sulphonimid of the formula:

in which R is an aromatic nucleus, and R is an acidyl radical obtained from a high molal detergent-forming monocarboxy acid having at least 8 carbon atoms and not more than 32 carbon at oms.

3. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a chemical compound within the molecular weight range of 536 to approximately 5,000, and of the formula:

Cation. s 03.01320 00.x"

in which R represents an alcoholic radical and at least one occurrence of R" being the dehydroxylated residue of an oxyethylated derivative of an acidyl-aryl-sulphonimid of the formula:

in which R is an aromatic nucleus, and R is an acidyl radical derived from a higher fatty acid having at least 8 carbon atoms and not more than 32 carbon atoms.

4. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a chemical compound within the molecular weight range of 536 to approximately 5,000, and of the formula:

Oation.SO;.CH.COO.R

' CH2.COO.R"

in which R" represents an alcoholic radical and at least one occurrence of R" being the dehydroxylated residue of an oxyethylated derivative of an acidyl-aryl-sulphonimid of the formula:

asom

. R in which R is an aromatic nucleus, and R is an acldyl radical obtained from a higher fatty acid having 18 carbon atoms.

5. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsi-,

fying agent comprising a chemical compound within the molecular weight range of 536 to approximately 5,000, and of the formula:

Cati0n.SO:.CH.OOO.R

* income."

in which R" represents an alcoholic radical and at least one occurrence of R"'being the dehydroxylated residue of an oxyethylated derivative of an acidyl-aryl-sulphonimid of the formula:

in which R is an aromatic nucleus, and R is an 7 acidyl radical obtained from an unsaturated higher fatty acid having 18 carbon atoms.

6. A process for breaking petroleum emulsions of the waer-in-oil type, characterized' by subjecting the emulsion to the action of a demulsifying agent comprising a chemical compound within the molecular weight range of 536 to ap proximately 5,000, and of the formula:

Cation.SO .CH.CO on" mooon" in whichR" represents an alcoholic radical and at least one occurrence of B." being the dehydroxylated residue of an oxyethylated derivative of an acidyl-aryl-sulphonimid of the formula R.s0,.N

R in which R is a monocyclic aromatic nucleus, and R is an acidyl radical obtained from an unsaturated higher fatty acid having 18 carbon atoms.

7. A. .process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsiiying agent comprising a water-soluble chemical compound within the molecular weight range of 536 to approximately 5,000, and of the formula:

canonsotomc o 0.1:"

Hg.COO.R"

urated higher fatty acid having 18 carbon at-' oms.

8. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a water-soluble chemical compound within the molecular weight range of 536 to approximately 5,000, and of the formula: v

Qation.S0a.CH.COO.R/'

in which both occurrences of R" represent the dehydroxylated residue of an oxyethylated'derivative of an acidyl aryl-sulphonimid of the formula:

in which R is a monocyclic aromatic nucleus, and R is an acidyl radical obtained from an unsaturated higher fatty acid having 18 carbon atoms.

MELVIN DE GROOTE.

BERNHARD KEISERF 

